The invention relates to a sound-absorbing, irregularly shaped panel of nonwoven fabric of polyester fibers.
A sound-absorbing, irregularly shaped panel of nonwoven fabric is described in DE-OS 25 10 607. It is used in the engine space of a motor vehicle and is reinforced by a heat hardening resin or by thermoplastic fibers. When using the resin, undesirable clogging of part of the pore volume of the fabric fibers must be tolerated, which reduces effectiveness. Use of thermoplastic fibers causes a reduction of the shape stability as a function of increasing temperature. With both, there is an undesirable increase in weight due to the penetration of moisture.
It is therefore an object of the invention to develop a sound-absorbing panel for use in the engine compartment of a motor vehicle which exhibits a high degree of sound absorption as well as shape stability under the influence of rising temperatures. These properties are understood to mean in particular that vibrations in a frequency range of 500 to 2000 Hz are more than 50 percent absorbed and that permanent changes of shape do not occur up to a temperature of 100.degree. C. when the panel is suspended under the hood of a motor vehicle and is anchored exclusively in the vicinity of the edges of the hood.